it does work now

restoring_division.c

#include <stdio.h>

#define BYTE_TO_BINARY_PATTERN "%c%c%c%c%c%c%c%c"
#define BYTE_TO_BINARY(byte)  \
  (byte & 0x80 ? '1' : '0'), \
  (byte & 0x40 ? '1' : '0'), \
  (byte & 0x20 ? '1' : '0'), \
  (byte & 0x10 ? '1' : '0'), \
  (byte & 0x08 ? '1' : '0'), \
  (byte & 0x04 ? '1' : '0'), \
  (byte & 0x02 ? '1' : '0'), \
  (byte & 0x01 ? '1' : '0') 

int main()
{
    printf("Hello World\n");
    int dividend = 63;  // N
    int divisor = 4;    // D
    
    int n = 6;  // number of bits in dividend
    
    int N = 63;
    int D = 4;
    int Q = N;
    int P = N;
    
    printf(" i\t| D\t| Q\t | P\n");
    
    D = D << n;
    //printf(" x\t| %d\t| %d\t| %d\n", D, Q, P);
    printf(" x");
    printf("\t| %d ", D); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(D&0xff));
    printf("\t| %d ", Q); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(Q&0xff));
    printf("\t| %d\t ", P); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(P&0xff));
    printf("\n");
    for(int i=(n-1); i >= 0; i--){
        
        P = 2*P - D;
        //printf(" %d\t| %d\t| %d\t| %d\n", i, D, Q, P);
        printf(" %d", i);
        printf("\t| %d ", D); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(D&0xff));
        printf("\t| %d ", Q); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(Q&0xff));
        printf("\t| %d\t ", P); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(P&0xff));
        printf("\n");
        if(P>=0){
            Q |= (1 << i);
        } else {
            Q &= ~(1 << i);
            P = P + D;
        }
        //printf(" %d\t| %d\t| %d\t| %d\n", i, D, Q, P);
        printf(" %d", i);
        printf("\t| %d ", D); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(D&0xff));
        printf("\t| %d ", Q); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(Q&0xff));
        printf("\t| %d\t ", P); printf(BYTE_TO_BINARY_PATTERN, BYTE_TO_BINARY(P&0xff));
        printf("\n");
    }
    
    D = D >> n;
    int R = N - Q*D;
    
    printf("%d / %d = %d, R:%d\n", N, D, Q, R);

    return 0;
}